Stabilizer for guns



June 13, 1944.

s. G. GREEN 2,351,037

STABILIZER FOR GUNS Filed OCT.. le. 1956 @lq-L' EaTrLuElB-ErEE1-L y fwn/af Attpr-ney Patented June 13, 1944 UNITED STATES PATENT OFFICE (Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 0. G. 757) Claims.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, Without the payment to me of any royalty thereon.

This invention relates to a stabilizer for guns and more particularly it has reference to a muzzle attachment serving to check recoil, silence the report, eliminate smoke and conceal ash.

It is generally recognized that only about 70% of the energy of the gases of the propelling charge is used in propelling the projectile. The unused balance escaping through the muzzle into atmosphere produces noise, smoke and flash, and impairs stability and accuracy. The velocity and pressure curves of the gases show that the unused energy is represented mainly by the velocity component which is much greater than the pressure component at the muzzle.

The purpose of this invention is to provide a stabilizer in which the velocity component of the gases is reduced at a more rapid rate than the pressure component so that their energy values will be about equal when the gases are discharged into the atmposphere. IIhe velocity of the gases is reduced until it is in the vicinity of the velocity of sound. While accomplishing the foregoing control of Velocity and pressure through the expansion and recompression cycles, the unburned powder is consumed and heat is maintained suiciently high within the combustable range to burn the residue and remaining gases and yet control the temperature below the detonating point.

With the foregoing and other objects in view, the invention resides in the novel arrangement and combination of parts and in the details of construction hereinafter described and claimed, itbeing understood that changes in the precise embodiment of the invention herein disclosed may be made within the scope of what is claimed Without departing from the spirit of the invention.

A practical embodiment of the invention is illustrated in the accompanying drawing, wherein:

Fig. 1 is a longitudinal sectional view of a stabilizer constructed in accordance with the invention.

Figs. 2, 3 and 4 are similar views of modified forms.

Referring to Fig. 1 there is shown a gun barrel 5 spaced from a surrounding jacket 6 which is of the air-cooled type.A An adapter 'l has a reduced rear part 8 inserted in the jacket and threaded thereto and also forming a bearing for the gun barrel. The front part of the adapter is formed with an enlarged bore to establish an impact chamber 9 directly in front of the muzzle of the gun barrel. A plug ID threaded in the front end of the adapter and constituting the front wall of the chamber 9 has a tapered entrance aperture II to permit passage of the bullet and the gases from the propelling charge.

The body of the stabilizer comprises a cylindrical member I2 open at its rear end and having a front wall I3 from which extends a flared tube I4 whose maximum diameter at its iront end is preferably less than the diameter of the cylindrical member I2. The open rear end of the member I2 is mounted on the adapter and attached thereto by a threaded connection I5. 'Ihe front wall I3 is spaced from the front wall I0 of the adapter to provide an expansion chamber I6. The iront wall I3 is formed with a central passage I1 and has an annular concave rear face I8 and an annular concave front face I9 which merges with the outer surface of the flared tube I4. A plurality of longitudinally disposed apertures 20 in the front wall I3 establish communication between the concave faces I8 and I9.

The fiared tube I 4 has a flared chamber 2I in continuation of the passage Il. The wall of the tube is provided with a plurality of radially disposed apertures 22. The tube I4 is disposed within and is spaced from a sleeve 23 which is cylindrical over the greater portion of its length and has its rear end mounted on the member I2 and attached thereto by a threaded connection 24. The front end 25 of the sleeve is turned in and meets the front end of the flared tube. It is provided with apertures 26 to vent the chamber 21 established between the sleeve and the ared tube. y

A baille ring 28 is carried internally by the sleeve and is positioned a short distance forwardly of the front wall I3 to establish a chamber 29. The inner face of the barile ring is spaced from the iiared tube I4 to permit flow of gases from the chamber 29 to the chamber 2T.

The approximate ratio between the volume of the chambers I 6, 2l and 21-29 is respectively one, two, three.

When a projectile is fired and emerges through the muzzle of the barrel, the gases of discharge enter the impact chamber 9 and build up pres sure therein Which reacts on the gun barrel to drive it rearwardly and thereby increase the speed of the breech bolt and associated parts of an automatic machine gun. At the same time the gases exert a forward pressure on the plug I which is part of the jacket 6 and the nonrecoiling elements of the gun and by tending to check recoil of these elements produce a sta- Y pand into the chamberII where they act on the wall I8 to maintain and augment the forwardv pressure on the non-recoiling elements of the gun. The expansion of the gases reduces their.`V tem erature, pressure and velocity. This champ 'asl'argeas the stabilizer of Fig. 2 which 1s for a ber serves as an initial combustion chamber for burning the unconsumed particles of the pro-v in its front portion in addition to the apertures @Tin its extremity.

In Fig. 4 the structure is similar to that of Fig.` 3 but has a cylindrical rst expansion chamber 48 and a sleeve 49 with an inturned flange 5D whereby it is threadedly attached to the stabilizerbody 5|..-

= .The drawings in Figs, 3 andjfl a k on a smaller scale than the drawingof Fig'. 2. They are intended for a .50 caliber gun ring long bursts 'and in actual size they are about one-half again l.gun normally firing short bursts.

pellent charge and the volatilized carbon' ofthe' gaSeS.

The carbon referred to in this application and present in the gases of discharge of the.A

' gun volatilizes and-flashes at a temperature be' forward pressure of the gases and breaks up flame propagation. The gasesfrom' ther chamberfZ!! flow intouthe second expansion chamber 21 whose cross-sectional areadecreases gradually towards its frontA end. The" purpose of constricting this chambertowardsits vents 26 is toproduce `gradual increase in pressure and to thereby raise the temperature to about' 1652J F. and. cause volatilized carbon to be consumed.

yThe gases passing through the'ared tube are vented intothe chamber 21 until the pressures 'are equali'zed. Since the tube I4 hasY an increasing volume towards Vits front the pressure 'and temperature of the gases are gradually reduced as they flow towards the exit and when discharged they are at lessv than combustion rteinperature. l

Stabilizers of 'this character are usually deisigned to cool the gases and dissipate heat and most-of them as `a result dischargethe gasesY to atmosphere as soon ras possible. According to the invention however 'the stabilizer is designed as a combustion member to consume the smoke and ashingredients of the gases before they are discharged into" the'at'mosphere.

The stabilizer of Fig. 1-l isrdesigned for use on a '.30 caliber machine gun which is intendedto.lireV long' bursts. l f

In Fig. ZVthereis'shown alstabilizerfor a .50 caliber machine gunl which .is intended to Ihre Iclaimz Y muzzlefattachmeht for a gun comprising .an `adapter securable to a gun and having a 'chamber'receiving `only the gases of discharge oi i the gun, said adapter having an apertured front wall, ya 4 body mounted onthe adapter and having a front wall spaced from the frontwall of the adapter and4 formed` with zannular kconcave front' and rear facsQfsaid front Wallfof4 th'eb'ody having a central 4passage and "circumferentially arranged throttling apertures,"`aiaredftube edf-"- tending from the front/ walloffjtheb'ody and formed with a-flared chamber-in 'continu'atinfcf the central passage ofthe loodyfSaLid.tubehavi'ng` aperturesjg'fi-nfit'sfwall; af slerlfve'rriunted on the b and having a turned-infront endY engaging fr'ont `end Yof V'the flaredV tube, said'tube and sleeve providing a' forwardly constricted chamber with'faf gas outlet at itSIfrQ'nt-end, and "bme ring on the sleeve spaced fronrthe 'flaredtpbe and'from the'front'wall 'of the body.v *i

A muzzle' ttachment fo a' 'gun'co'mprisin'g an adapter-securable'fto a gun and' havingr^a chamber receiving'only the gases of'discharg of the gun, said adapterhav'ing an apertured `from; wall, a-bodymounted on the adapter andY having afront wall spaced from the front l'vi/all''ofthe adapter and Aformed with annular' conc'aveffrbnt and rearfacea vsaid front Iwall ofthe body having Central fpflssg @lid clffrfily gj t ng a gas outlet 'at itsVV front end.

` 3. A muzzleattachment fo'rfafl guri'conipris'ing anf adapter securable 'to' a gun and having IYa chamber receiving only thejgasesjofdischaifge of thegun, saidadapter"havingfanapertured short bursts. In this design the impact; chamber tube 38 and conduct gasesfro'm a's'mallchamber 39 in the tube 38 to the chamber 34.

In Fig. 3 the stabilizer body fifis mounted yon a part of the water jacket 4I. and .has'a flared expansion chamber 42. The central bullet pas'- sage 43 has its origin in abushing 44 of `heatresisting metal.v The sleeve 45 has apertures 46 front wall. af bodyY mountedon Ithe adapter and havinga front wallspaced from the frontwalfl of-thejadapterpsaidlfront wall of thebdy'havj ing a 'central passagev and V`circum.ferentially' arranged throttling' apertures, a aredtube extend,- ing from the rfront Wall of the body andwform'ed witha flaredchamber in'contiruatioroith tral'passagejofthebodyfs tures in Aits "wall, ai sleeve; m

Medionl theabo'dy,

and Vsaid" tube and 'sleevepoviding aforwardly constricted chamber with a gasoutlet .at it en d .l in 4. In a muzzle attachment fora gun, a ng securable to a'gun' so as to receive'only' the-gases of discharge'of the gun-and 'having wallsifo'rin ing a seriesof chambersjincludihg animpact chamber,` an expansion-chamber in' front' of the impact chamber; an= inner flared chamber and all 'Quterf forwardly constricted 'chamber-"both disposed forwardly of the expansion chamber, the inner and outer chambers being in communication with each other and with the expansion chamber, and means for venting the outer constricted chamber at its front end, the ratio in the volume of the expansion chamber, the inner flared chamber and the outer constricted chamber being respectively about one, two, three.

5. In a muzzle attachment for a gun, means securable to a gun adjacent the muzzle thereof so as to receive only the gases of discharge of the gun, said means comprising a cylindrical expansion chamber, an inner chamber and an outer forwardly constricted chamber both disposed forwardly of the expansion chamber, the walls forming said inner and outer chambers being secured to eachV otllenadjacentV their forward ends, said walls being provided with ports establishing intercommunication between each of said chambers, and means for venting the outer constricted chamber at its front end directly to the atmosphere, the ratio in the volume of the expansion chamber, the inner flared chamber and the outer constricted chamber being respectively about one, two, three.

6. In a muzzle attachment for a gun, means securable to a gun adjacent the muzzle thereof so as to receive only the gases of discharge of the gun, said means comprising a cylindrical expansion chamber, an inner chamber and an outer forwardly constricted chamber both disposed forwardly of the expansion chamber, the walls forming said inner and outer chambers being secured to each other adjacent their forward ends, said walls being provided with ports establishing inter-communication between each of said chambers, and means for venting the outer constricted chamber at its front end directly to the atmosphere.

7. In a muzzle attachment for a gun, means securable to a gun and having a closed rear end so as to receive only the gases of discharge of the gun, said means comprising a cylindrical expansion chamber, a flared chamber, and a forwardly constricted chamber having an outlet at its small end venting directly to the atmosphere, means for throttling some of the gases out of said expansion chamber, into said forwardly constricted chamber, said constricted chamber being adapted to compress the gases it receives from the expansion chamber to increase their temperature and insure a temperature above 925 F., said flared chamber being in communication with the constricted chamber and receiving some of the gases from the expansion chamber and serving to decrease the pressure and temperature of the gases and the walls forming said forwardly constricted and iiared chambers being secured to each other adjacent their forward ends.

8. In a muzzle attachment for a gun, a casing securable to a gun and having a closed rear end so as to receive only the gases of discharge of the gun and having a central bullet passage and comprising a cylindrical expansion chamber, a forwardly constricted chamber annularly positioned relative to the said central bullet passage and provided with a plurality of openings in communication therewith to receive some of the gases and having an outlet at its small end venting directly to the atmosphere, said constricted chamber serving by compression of the gases to increase their temperature and insure a temperature alcove 925 F., and a flared chamber in communication with the constricted chamber and receiving some of the gases from the expansion chamber and serving to decrease the pressure and temperature of the gases the walls formingn the forwardly constricted and flared chambers being secured to each other adjacent their forward ends.

9. A compensating device for attachment to the muzzle of rearms and to receive the gases of explosion issuing therefrom, said device comprising a pair of serially connected and coaxial chambers as well as a third chamber encompassing portions of the pair of chambers, all of said chambers having substantially cylindrical portions and having a projectile opening at an end thereof, said chambers also having gas conducting passages therebetween, the walls at the forward end of the encompassing chamber having a forwardly converging and apertured interior surface extending from the cylindrical portion thereof forwardly and inwardly to the projectile opening thereof to increase the pressure of the forwardly moving gases, the forward wall portion of one of said pair of chambers having an inwardly directed interior surface extending from the cylindrical portion thereof inwardly substantially to the projectile opening thereof.

10. A compensating device for attachment to the muzzle of firearms and to receive the gases of explosion issuing therefrom, said device comprising a pair of serially connected and coaxial chambers as well as a third chamber encompassing portions of the pair of chambers, all of said chambers having substantially cylindrical portions and having a projectile opening at an end thereof, said chambers also having gas conducting passages therebetween, the walls at the forward end of the encompassing chamber having a forwardly converging and apertured interior surface extending from the cylindrical portion thereof forwardly and inwardly to the projectile opening thereof to increase the pressure of the forwardly moving gases, the forward wall portion of one of said pair of chambers having a converging interior surface extending from the cylindrical portion thereof inwardly and provided with a central projectile opening.

SAMUEL G. GREEN. 

